Sake, Soy Sauce, and the Taming of the Microbes

What do beer, dogs and cats, and corn all have in common? All of them are the end products of the process of domestication. Almost everybody knows that a number of different animals and plants have been bred for qualities that benefit humans. But few people realize that a number of microbes have undergone a similar transformation.

Take brewer's yeast, for example. It is the quintessential ingredient in beer making: genetically altered to convert the sugars in malted barley into alcohol and to produce metabolic byproducts that give beer its unique taste. In fact, dozens of specialized strains of yeast produce the wide variety of beers, lagers and ales that brewers have developed.

"Although people don't often think about it, we haven't only domesticated animals and plants, but we have also domesticated dozens of different microbes," said Assistant Professor of Biological Sciences Antonis Rokas, adding that it's hard to imagine what life would be like without beer, wine, leavened bread, cheese, yoghurt, soy sauce, sauerkraut and a number of other mainstays of the human diet that are produced by domesticated microbes.

"The genetic basis for the domestication of many different plants and animals has been extensively studied, but, remarkably, very little is known about how domestication has shaped the genetic makeup of microbes," he said.